Valve and diaphragm for a pump

ABSTRACT

A diaphragm pump ( 10 ) having a pump body ( 11 ) providing opposing pump chambers ( 12, 13 ). Mounted in the body is a piston assembly ( 14 ) having pistons ( 15 ) joined by a piston rod ( 16 ). Each piston ( 15 ) is sealingly connected to the body ( 11 ) by a diaphragm ( 22 ) so that each of the chambers ( 12, 13 ) is divided into a first and a second sub-chamber, with the flow of fluid being pumped is governed by a pair of valves ( 30 ). Each valve ( 30 ) includes a base ( 31 ) to which there is movably attached a movable valve member ( 35 ).

This patent application claims the benefit of Australian ProvisionalPatent Application No. 2008902425 filed May 16, 2008.

TECHNICAL FIELD

The present invention relates to valves and diaphragms for diaphragmpumps that are operated by a working fluid under pressure.

BACKGROUND OF THE INVENTION

Diaphragm pumps include a pump chamber that is divided by a piston ordiaphragm so as to provide a first sub-chamber that receives a workingfluid (liquid or gas) under pressure, and a second sub-chamber thatreceives the fluid being pumped. A working fluid under pressure isdelivered to the first sub-chamber to cause reciprocation of the pistonand diaphragm to vary the volume of the second sub-chamber and therebypump a fluid therethrough. These diaphragm pumps have an inlet and anoutlet that communicate with the second sub-chamber via one-way valvesso that the fluid being pumped passes in a predetermined directionthrough the pump. A first manifold joins the inlet with the secondsub-chamber while a second manifold joins the second sub-chamber withthe outlet.

The above manifolds are sealingly connected to the pump body by a meansof seal.

The above mentioned one-way valves are mounted on the body.

A disadvantage of the above described pump is that it is typical tosealingly connect the manifolds to the pump body while the one-wayvalves are separately mounted to engage the associated valve seat.

The above-mentioned diaphragm when performing at pumping action iscaused to undergo substantial elastic deformation. A disadvantage ofthese known diaphragms is that they are prone to failure.

OBJECT OF THE INVENTION

It is the object of the present invention to overcome or substantiallyameliorate at least one of the above disadvantages.

SUMMARY OF THE INVENTION

There is firstly disclosed herein a valve for a pump, the valve beingintegrally formed of plastics material and including:

an elongated base via which the valve is to be mounted in the pump, thebase being of a loop configuration so as to have a pair of transverselyspaced elongated side portions joined by longitudinally spaced endportions;

a movable valve member located adjacent one of said end portions andconfigured to sealingly cooperate with a valve seat of the pump to closea valve opening provided by the seat; and

a flexible bridge pivotally coupling the movable valve member with saidone end portion providing for movement of the valve member by resilientdeformation of the bridge.

Preferably, said bridge includes a first bridge portion and a secondbridge portion, the bridge portions being transversely spaced.

Preferably, said side portions are substantially co-extensive and saidend portions are substantially co-extensive.

Preferably, said end portions are arcuate in configuration.

Preferably, said base in transverse cross-section is arcuate so as toprovide a concave surface and a convex surface.

Preferably, said base in transverse cross-section is of a “C”configuration.

Preferably, said bridge provides a pivot axis extending generallytransverse relative to said base.

There is further disclosed herein a diaphragm for a diaphragm pump, thepump having a pump body and a pump piston that is reciprocated relativeto the body along a longitudinal axis, with said diaphragm beingconfigured to extend between said piston and said body, said diaphragmincluding:

a base to be fixed to the piston;

a radially outer peripheral portion to be fixed to the body;

a flexible diaphragm portion extending between the base and saidperipheral portion, said diaphragm portion having a first set ofsegments and a second set of segments alternately spaced with respect tothe first set segments, the segments each extending angularly about andradially relative to said axis, and wherein

the first segments are spaced longitudinally relative to said axis fromthe second segments.

Preferably, said diaphragm is integrally formed from flexible plasticsmaterial.

Preferably, said first segments are attached to said second segments byhinge portions, the hinge portions having a thickness less thanthicknesses of the first and second portions to provide for relativemovement between the first and second segments by resilient deformationof the hinge portions.

Preferably, said first segments have a thickness greater than the secondsegments so that the second segments during operation of the diaphragmmove relative to the first segments by resilient deformation at andadjacent hinge lines separating the first and second segments.

There is disclosed herein a pump having:

a pump body providing a pump chamber;

a piston movably mounted in the body for reciprocation relative to thebody;

a diaphragm sealingly connecting the piston to the body so as to dividesaid chamber into a first sub-chamber and a second sub-chamber;

first ducting, said first ducting being in communication with said firstchamber to provide for the flow of a pumped fluid to and from said firstchamber;

second ducting, said second ducting being in communication with saidsecond sub-chamber to provide for the flow of a working fluid to andfrom said second chamber to cause the reciprocation of said piston;

a first valve in said first ducting and upstream of said firstsub-chamber, and a second valve in said first ducting downstream of saidfirst sub-chamber, the first and second valves governing the flow of thepumped fluid to and from said first sub-chamber to cause the pumpedfluid to move in a pumped direction; and wherein

each valve is a valve as described above.

Preferably, said diaphragm is a diaphragm as described above.

There is still further disclosed herein a pump having:

a pump body providing a pump chamber;

a pump movably mounted in the body for reciprocation relative to thebody;

a diaphragm sealingly connecting the piston to the body so as to dividethe chamber into a first sub-chamber and a second sub-chamber;

first ducting, said first ducting being in communication with saidsub-chamber to provide for the flow of a pumped fluid to and from saidfirst sub-chamber;

second ducting, said second ducting being in communication with saidsecond sub-chamber to provide for the flow of a working fluid to andfrom said second sub-chamber to cause the reciprocation of said piston;

a first valve in said first said ducting and upstream of said firstsub-chamber, and a second valve in said first ducting downstream of saidfirst chamber, the first and second valves governing the flow of thepumped fluid to and from said first sub-chamber to cause the pumpedfluid to move in a pumped direction; and wherein

said diaphragm is a diaphragm as described above.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred form of the present invention will now be described, by wayof an example only, with reference to the accompanying drawings wherein:

FIG. 1 is a schematic sectioned side elevation of a diaphragm pump;

FIG. 2 is a schematic further sectioned side elevation of the pump ofFIG. 1;

FIG. 3 is a schematic plan view of a valve employed in a pump of FIG. 1;

FIG. 4 is a schematic sectioned side elevation of the valve of FIG. 3;

FIG. 5 is a schematic sectioned end elevation of the valve of FIG. 3;

FIG. 6 is a schematic plan view of a diaphragm employed in a pump ofFIG. 1;

FIG. 7 is a schematic sectioned side elevation of the diaphragm of FIG.6;

FIG. 8 is a schematic enlarged sectioned elevation of portion of thediaphragm as shown in FIG. 7; and

FIG. 9 is a schematic enlarged sectioned elevation of portion of thediaphragm as shown in Figure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the accompanying drawings, there is schematically depicted adiaphragm pump 10. The pump 10 includes a pump body 11 that provides apair of opposed pump chambers 12 and 13. Mounted in the body 11 is apiston assembly 14 providing a pair of pistons 15 joined by a transversepiston rod 16 so that the pistons 15 are caused to reciprocate in unisonlinearly in the direction 17 along the axis 18. The piston rod 16 andpistons 15 have as their longitudinal axis the longitudinal axis 18. Thebody 11 includes a base 20 providing a pair of cup portions 19. Securedto each cup portion 19 is a sleeve 21, with the cup portions 19 andassociated sleeves 19 cooperating to provide the chambers 12 and 13.

The piston rod 16 is slidably mounted in the cup portions 19.

Fixed to each piston 15 is a diaphragm 22 that together with theassociated piston 15 divides the respective chamber 12 or 13 into afirst sub-chamber 23 and a second sub-chamber 24. A working fluid(liquid or gas) under pressure is alternately delivered to thesub-chambers 23 to cause reciprocation of the piston assembly 14.Accordingly the pump 10 could be hydraulically or pneumatically driven.

Schematically depicted is a control valve 25 and associated ducting thatdelivers the working fluid to the sub-chambers 23 and provides fordrainage of the working fluid therefrom as the chambers 23 are varied involume.

The pump 10 has an inlet 26 to which a fluid being pumped is delivered,and an outlet 27 to which the fluid being pumped is delivered underpressure by the pump 10. The inlet 26 communicates with bothsub-chambers 24 while the outlet 27 also communicates with bothsub-chambers 24. More particularly, the inlet 26 is joined to thesub-chamber 24 by a manifold 28. While each outlet 27 is joined to thesub-chamber 24 by a manifold 29.

To ensure that the fluid being pumped passes in a predetermineddirection through the pump 10 there is provided one-way valves 30.

One of the one-way valves 30 is best seen in FIGS. 3 to 5. Each one-wayvalve 30 is integrally formed of resilient plastics material andprovides for the control of fluid being pumped through the valve 10while also sealingly connecting the associated manifold 28/29 with thebody 11. Each valve 30 includes an elongated base 31 that has alongitudinal axis 32. The base 31 has a pair of longitudinally extendingside portions 33 that are substantially co-extensive and aretransversely spaced relative to the axis 32. Joining the side portions33 are end portions 34 that are spaced longitudinally relative to theaxis 32 and extend generally transverse of the axis 32. Each end portion34 is generally arcuate in configuration.

The base 31 provides a seal between the associated manifold 28 andsleeve 21.

Each valve 30 further includes a movable valve member 35 that is causedto move relative to an associated valve seat 36 (provided by the body11) providing a valve opening 37. In particular, each member 35 iscaused to move between an opened position providing for flow through theassociated valve opening 37, and a closed position preventing flowthrough the valve opening 37 in the reverse direction.

Each valve member 35 is generally circular in configuration and has anannular convex surface 38 that engages the associated valve seat 36.Generally centrally of the valve member 35 and surrounded by the surface38 is a depression 57. When the valve member 35 is in an open position,the depression 57 aids in providing a bigger aperture for fluid flow.Each member 35 is attached to an adjacent end portion 34 by a bridge 39.By resilient deformation of the bridge 39 the member 35 is able to moverelative to the associated valve seat 36. Each bridge 39 includes a pairof transversely spaced elongated bridge portions 40 that extendgenerally parallel to the axis 32 and provide for angular movement ofthe valve member 25 about a transverse axis 41.

Preferably, the base 31 in transverse cross-section is arcuate, and moreparticularly is of a “C” configuration. Accordingly, the base 33provides a convex surface 42 and a convex surface 43.

As best seen in FIG. 3 the base 33 is a closed loop surrounding anaperture 44 within which the member 35 is located.

The diaphragm 22 is illustrated in FIGS. 6, 7, 8 and 9.

The diaphragm 22 includes a central base 45 that is of an annularconfiguration so as to provide a central aperture 46. The base 45 has aplurality of ribs 47 that aid in securing and sealing the diaphragm 22to the associated piston 15. In particular, the base 45 extends radiallyfrom and angularly about the axis 18 and is generally planar. The base45 is of an annular configuration so that its longitudinal axis is alsothe axis 18.

The diaphragm 22 has a peripheral portion 48 fixed to the body 20.Extending between the base 45 and periphery 48 is a diaphragm portion49. The diaphragm portion 49 is also annular and has first radially andangularly extending segments 50 and second radially and angularlyextending segments 51. The segments 51 are further displaced from thebase 45 in the direction of the axis 18 than the segments 50.

The segments 50 have a greater width 52 than the corresponding width 53of the segments 51. The segments 50 and 51 are joined by hinge portions54 that separate the segments 50 and 51. The hinge portions 54 providefor relative movement between the segments 50 and 51 by resilientdeformation of the hinge portions 54. This relative movement is providedby resilient deformation of the diaphragm portion 49 adjacent the hingelines 54.

As best seen in FIG. 6, the segments 51 also extend angularly about theaxis 18.

Each diaphragm 22 is integrally formed from the resiliently plasticsmaterial.

Preferably, each valve 30 and each diaphragm 22 is molded from resilientplastics material.

In operation of the above described pump 10 a working fluid underpressure is alternatively delivered to the first sub-chambers 23 byoperation of a valve 25. This causes reciprocation of the pistonassembly 14 thereby varying the volume of the sub-chambers 23 as well asthe sub-chambers 24. A fluid being pumped is delivered to the inlet 26wherefrom it flows to the sub-chambers 24 from the one-way valves 30.The fluid being pumped is drawn into each sub-chamber 24 as the volumethereof is being increased. As the volume of each sub-chamber 24decreases the fluid being pumped is delivered to the outlet 27 again viathe associated one-way valve 30.

The one-way valves 30 are located at an appropriate orientation toprovide for flow in an inlet direction or an outlet direction dependingon their location for the purposes of providing for fluid through thepump 10.

Each piston 15 includes a mounting flange 55 and an associated clampplate 56 secured thereto so that the base 45 of the associated diaphragmis clamped between the associated mounting flange 55 and clamp plate 56.

Although the invention has been described with reference to specificexamples, it will be appreciated by those skilled in the art that theinvention may be embodied in many other forms.

The invention claimed is:
 1. A pump comprising: a pump body providing apump chamber, an inlet valve seat and an outlet valve seat providing forflow of a pumped liquid in and out of the chamber; a piston movablymounted in the pump body for reciprocation relative to the pump body; adiaphragm sealingly connecting the piston to the pump body so as todivide said chamber into a first sub-chamber and a second sub-chamber;an inlet manifold providing first ducting, said first ducting being incommunication with said first sub-chamber to provide for the flow of thepumped liquid to and from said first sub-chamber from said inlet valveseat; an outlet manifold providing second ducting, the second ductingproviding for flow of the pumped liquid from the first sub-chamber viathe outlet valve seat; third ducting, said third ducting being incommunication with said second sub-chamber to provide for the flow of aworking fluid to and from said second sub-chamber to cause thereciprocation of said piston; a first valve associated with said firstducting and upstream of said first sub-chamber so as to be locatedbetween the inlet valve seat and first sub-chamber, and a second valveassociated with said second ducting so as to be located downstream ofsaid first sub-chamber, the first and second valves governing the flowof the pumped liquid to and from said first sub-chamber to cause thepumped liquid to move in a pumped direction; and wherein each valve isintegrally formed of plastics material and includes: an elongated basesealingly connecting, and coupled between, the pump body and arespective manifold, the base being of a looped configuration andcomprising an elongated aperture so as to have a pair of transverselyspaced elongated longitudinal side portions joined by longitudinallyspaced transverse end portions; a movable valve member located adjacentone of said end portions and configured to sealingly cooperate with arespective valve seat of the pump body to close a valve opening providedby the respective seat; a flexible bridge coupling the movable valvemember with said one end portion providing, for movement of the valvemember by resilient deformation of the bridge; and with said firstducting extending from the inlet valve seat to the first sub-chamber sothat the valve associated with the inlet valve seat is located betweenthe inlet valve seat and the first sub-chamber.
 2. The pump of claim 1,wherein said bridge includes a first bridge portion and a second bridgeportion, the bridge portions being transversely spaced.
 3. The pump ofclaim 1, wherein said side portions are substantially co-extensive andsaid end portions are substantially co-extensive.
 4. The pump of claim1, wherein said end portions are arcuate in configuration.
 5. The pumpof claim 1, wherein said base in transverse cross-section is arcuate soas to provide a concave surface and a convex surface.
 6. The pump ofclaim 3, wherein said base in transverse cross-section is of a “C”configuration.
 7. The pump of claim 3, wherein said bridge provides apivot axis extending generally transverse relative to said base.
 8. Thepump of claim 1, wherein the second ducting extends downstream from thesecond valve seat to an outlet.
 9. The pump of claim 1, wherein an inletextends to the inlet valve seat.